Array slice function that works with associative arrays (keys):
function array_slice_assoc($array,$keys) {
return array_intersect_key($array,array_flip($keys));
}
(PHP 4, PHP 5, PHP 7, PHP 8)
array_slice — 配列の一部を展開する
array_slice()は、array
から引数 offset
および
length
で指定された連続する要素を返します。
array
入力の配列。
offset
offset
が負の値ではない場合、要素位置の計算は、
配列 array
の offset から始められます。
offset
が負の場合、要素位置の計算は
array
の最後から行われます。
offset
は、配列の位置を表します。配列のキーではありません。
length
length
が指定され、正の場合、
配列の要素の中から最大でその数までの要素を返します。
配列の要素数が length
より少ない場合は、
配列から取得できる要素だけを返します。
length
が指定され、負の場合、配列の末尾からその数だけ要素を取り除いた配列が返されます。
省略された場合、offset
から配列の最後までの全ての要素が返されます。
preserve_keys
注意:
array_slice() はデフォルトで配列の数値キーを並べなおし、 リセットします。
preserve_keys
をtrue
にする事でこの動作を変更することができます。 文字列のキーは、このパラメータの値にかかわらず常に保存されます。
切り取った部分を返します。オフセットが配列のサイズより大きい場合は、空の配列を返します。
例1 array_slice() の例
<?php
$input = array("a", "b", "c", "d", "e");
$output = array_slice($input, 2); // "c", "d", "e" を返す
$output = array_slice($input, -2, 1); // "d" を返す
$output = array_slice($input, 0, 3); // "a", "b", "c" を返す
// 配列キーの違いに注意
print_r(array_slice($input, 2, -1));
print_r(array_slice($input, 2, -1, true));
?>
上の例の出力は以下となります。
Array ( [0] => c [1] => d ) Array ( [2] => c [3] => d )
例2 array_slice() と、キーが1から始まる配列
<?php
$input = array(1 => "a", "b", "c", "d", "e");
print_r(array_slice($input, 1, 2));
?>
上の例の出力は以下となります。
Array ( [0] => b [1] => c )
例3 array_slice() に、数値と文字列のキーが混じった配列を渡す例
<?php
$ar = array('a'=>'apple', 'b'=>'banana', '42'=>'pear', 'd'=>'orange');
print_r(array_slice($ar, 0, 3));
print_r(array_slice($ar, 0, 3, true));
?>
上の例の出力は以下となります。
Array ( [a] => apple [b] => banana [0] => pear ) Array ( [a] => apple [b] => banana [42] => pear )
Array slice function that works with associative arrays (keys):
function array_slice_assoc($array,$keys) {
return array_intersect_key($array,array_flip($keys));
}
If you want an associative version of this you can do the following:
function array_slice_assoc($array,$keys) {
return array_intersect_key($array,array_flip($keys));
}
However, if you want an inverse associative version of this, just use array_diff_key instead of array_intersect_key.
function array_slice_assoc_inverse($array,$keys) {
return array_diff_key($array,array_flip($keys));
}
Example:
$arr = [
'name' => 'Nathan',
'age' => 20,
'height' => 6
];
array_slice_assoc($arr, ['name','age']);
will return
Array (
'name' = 'Nathan',
'age' = 20
)
Where as
array_slice_assoc_inverse($arr, ['name']);
will return
Array (
'age' = 20,
'height' = 6
)
<?php
// CHOP $num ELEMENTS OFF THE FRONT OF AN ARRAY
// RETURN THE CHOP, SHORTENING THE SUBJECT ARRAY
function array_chop(&$arr, $num)
{
$ret = array_slice($arr, 0, $num);
$arr = array_slice($arr, $num);
return $ret;
}
based on worldclimb's arem(), here is a recursive array value removal tool that can work with multidimensional arrays.
function remove_from_array($array,$value){
$clear = true;
$holding=array();
foreach($array as $k => $v){
if (is_array($v)) {
$holding [$k] = remove_from_array ($v, $value);
}
elseif ($value == $v) {
$clear = false;
}
elseif($value != $v){
$holding[$k]=$v; // removes an item by combing through the array in order and saving the good stuff
}
}
if ($clear) return $holding; // only pass back the holding array if we didn't find the value
}
array_slice can be used to remove elements from an array but it's pretty simple to use a custom function.
One day array_remove() might become part of PHP and will likely be a reserved function name, hence the unobvious choice for this function's names.
<?
function arem($array,$value){
$holding=array();
foreach($array as $k => $v){
if($value!=$v){
$holding[$k]=$v;
}
}
return $holding;
}
function akrem($array,$key){
$holding=array();
foreach($array as $k => $v){
if($key!=$k){
$holding[$k]=$v;
}
}
return $holding;
}
$lunch = array('sandwich' => 'cheese', 'cookie'=>'oatmeal','drink' => 'tea','fruit' => 'apple');
echo '<pre>';
print_r($lunch);
$lunch=arem($lunch,'apple');
print_r($lunch);
$lunch=akrem($lunch,'sandwich');
print_r($lunch);
echo '</pre>';
?>
(remove 9's in email)
remember that array_slice returns an array with the current element. you must use array_slice($array, $index+1) if you want to get the next elements.
Using the varname function referenced from the array_search page, submitted by dcez at land dot ru. I created a multi-dimensional array splice function. It's usage is like so:
$array['admin'] = array('blah1', 'blah2');
$array['voice'] = array('blah3', 'blah4');
array_cut('blah4', $array);
...Would strip blah4 from the array, no matter where the position of it was in the array ^^ Returning this...
Array ( [admin] => Array ( [0] => blah1 [1] => blah2 ) [voice] => Array ( [0] => blah3 ) )
Here is the code...
<?php
function varname ($var)
{
// varname function by dcez at land dot ru
return (isset($var)) ? array_search($var, $GLOBALS) : false;
}
function array_cut($needle, $haystack)
{
foreach ($haystack as $k => $v)
{
for ($i=0; $i<count($v); $i++)
if ($v[$i] === $needle)
{
return array_splice($GLOBALS[varname($haystack)][$k], $i, 1);
break; break;
}
}
?>
Check out dreamevilconcept's forum for more innovative creations!
The documentation doesn't say it, but if LENGTH is ZERO, then the result is an empty array [].
To save the sort order of a numeric index in the array. Version php =>5.5.26
/*
Example
*/
$arr = array( "1" =>2, "2" =>3 , "3" =>5 );
print_r(array_slice($arr,1,null,true));
/*
Result
Array
(
[2] => 3
[3] => 5
)
*/
<?php
// Combines two arrays by inserting one into the other at a given position then returns the result
function array_insert($src, $dest, $pos) {
if (!is_array($src) || !is_array($dest) || $pos <= 0) return FALSE;
return array_merge(array_slice($dest, 0, $pos), $src, array_slice($dest, $pos));
}
?>
If you specify the fourth argument (to not reassign the keys), then there appears to be no way to get the function to return all values to the end of the array. Assigning -0 or NULL or just putting two commas in a row won't return any results.
<?php
/**
* Reorders an array by keys according to a list of values.
* @param array $array the array to reorder. Passed by reference
* @param array $list the list to reorder by
* @param boolean $keepRest if set to FALSE, anything not in the $list array will be removed.
* @param boolean $prepend if set to TRUE, will prepend the remaining values instead of appending them
* @author xananax AT yelostudio DOT com
*/
function array_reorder(array &$array,array $list,$keepRest=TRUE,$prepend=FALSE,$preserveKeys=TRUE){
$temp = array();
foreach($list as $i){
if(isset($array[$i])){
$tempValue = array_slice(
$array,
array_search($i,array_keys($array)),
1,
$preserveKeys
);
$temp[$i] = array_shift($tempValue);
unset($array[$i]);
}
}
$array = $keepRest ?
($prepend?
$array+$temp
:$temp+$array
)
: $temp;
}
/** exemple ** /
$a = array(
'a' => 'a',
'b' => 'b',
'c' => 'c',
'd' => 'd',
'e' => 'e'
);
$order = array('c','b','a');
array_reorder($a,$order,TRUE);
echo '<pre>';
print_r($a);
echo '</pre>';
/** exemple end **/
?>
/**
* Remove a value from a array
* @param string $val
* @param array $arr
* @return array $array_remval
*/
function array_remval($val, &$arr)
{
$array_remval = $arr;
for($x=0;$x<count($array_remval);$x++)
{
$i=array_search($val,$array_remval);
if (is_numeric($i)) {
$array_temp = array_slice($array_remval, 0, $i );
$array_temp2 = array_slice($array_remval, $i+1, count($array_remval)-1 );
$array_remval = array_merge($array_temp, $array_temp2);
}
}
return $array_remval;
}
$stack=Array('apple','banana','pear','apple', 'cherry', 'apple');
array_remval("apple", $stack);
//output: Array('banana','pear', 'cherry')
Note that offset is not the same thing as key. Offset always starts at 0, while keys might be any number.
So this:
<?php print_r(array_slice(array(0 => 0, 5 => 5, 13 => 13),1)); ?>
will result in this:
Array
(
[0] => 5
[1] => 13
)
<?php
/**
* @desc
* Combines two arrays by inserting one into the other at a given position then
* returns the result.
*
* @since 2007/10/04
* @version v0.7 2007/10/04 18:47:52
* @author AexChecker <AexChecker@yahoo.com>
* @param array $source
* @param array $destination
* @param int [optional] $offset
* @param int [optional] $length
* @return array
*/
function array_insert($source, $destination, $offset = NULL, $length = NULL) {
if (!is_array($source) || empty($source)) {
if (is_array($destination) && !empty($destination)) {
return $destination;
}
return array();
}
if (is_null($offset)) {
return array_merge($destination, $source);
}
$offset = var2int($offset);
if (is_null($length)) {
if ($offset === 0) {
return array_merge($source, array_slice($destination, 1));
}
if ($offset === -1) {
return array_merge(array_slice($destination, 0, -1), $source);
}
return array_merge(
array_slice($destination, 0, $offset),
$source,
array_slice($destination, ++$offset)
);
}
if ($offset === 0) {
return array_merge($source, array_slice($destination, $length));
}
$destination_count = count($destination);
$length = var2int($length);
if ($offset > 0) {
if ($destination_count - $offset < 1) {
return array_merge($destination, $source);
}
} else{
if (($t = $destination_count + $offset) < 1) {
return array_merge($source, $destination);
}
$offset = $t;
}
if ($length > 0) {
$length+= $offset;
} elseif ($length < 0 && !($length * -1 < $destination_count)) {
return $source;
} else {
$length = $offset;
}
return array_merge(
array_slice($destination, 0, $offset),
$source,
array_slice($destination, $length)
);
}
?>
Sometimes you need to pick certain non-integer and/or non-sequential keys out of an array. Consider using the array_pick() implementation below to pull specific keys, in a specific order, out of a source array:
<?php
$a = array ('a' => 1, 'b' => 2, 'c' => 3, 'd' => 4);
$b = array_pick($a, array ('d', 'b'));
// now:
// $a = array ('a' => 1, 'c' => '3');
// $b = array ('d' => 4, 'b' => '2');
function &array_pick(&$array, $keys)
{
if (! is_array($array)) {
trigger_error('First parameter must be an array', E_USER_ERROR);
return false;
}
if (! (is_array($keys) || is_scalar($keys))) {
trigger_error('Second parameter must be an array of keys or a scalar key', E_USER_ERROR);
return false;
}
if (is_array($keys)) {
// nothing to do
} else if (is_scalar($keys)) {
$keys = array ($keys);
}
$resultArray = array ();
foreach ($keys as $key) {
if (is_scalar($key)) {
if (array_key_exists($key, $array)) {
$resultArray[$key] = $array[$key];
unset($array[$key]);
}
} else {
trigger_error('Supplied key is not scalar', E_USER_ERROR);
return false;
}
}
return $resultArray;
}
?>